The present invention relates to a new and distinct variety of white nectarine tree, Prunus persica L. Batsch var. nucipersica, which has been given the variety denomination ‘NECTARRUBY’. This new tree produces fruit with a long shelf life without alteration both on the tree after growth completion and after harvesting, very good eating quality, fresh fruit for fresh market in August in the Pyrénées-Orientales department, France. Contrast is made to ‘NECTAREXQUISE’ (U.S. Plant Pat. No. 19,377) white nectarine tree, standard variety, for reliable description. ‘NECTARRUBY’ is a promising candidate for commercial success in that it has an medium flowering, fruit with very long shelf life without alteration after harvesting, and so a very durable fruit.